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problems/graph-valid-tree/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/single-number-iii "Single Number III")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/trips-and-users "Trips and Users")
+
 ## 261. Graph Valid Tree (Medium)
 
 

problems/group-anagrams/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/rotate-image "Rotate Image")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/powx-n "Pow(x, n)")
+
 ## 49. Group Anagrams (Medium)
 
 <p>Given an array of strings, group anagrams together.</p>

problems/group-shifted-strings/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/strobogrammatic-number-iii "Strobogrammatic Number III")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/count-univalue-subtrees "Count Univalue Subtrees")
+
 ## 249. Group Shifted Strings (Medium)
 
 

problems/guess-number-higher-or-lower-ii/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/guess-number-higher-or-lower "Guess Number Higher or Lower")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/wiggle-subsequence "Wiggle Subsequence")
+
 ## 375. Guess Number Higher or Lower II (Medium)
 
 <p>We are playing the Guess Game. The game is as follows:</p>

problems/guess-number-higher-or-lower/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/find-k-pairs-with-smallest-sums "Find K Pairs with Smallest Sums")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/guess-number-higher-or-lower-ii "Guess Number Higher or Lower II")
+
 ## 374. Guess Number Higher or Lower (Easy)
 
 <p>We are playing the Guess Game. The game is as follows:</p>

problems/hamming-distance/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/lfu-cache "LFU Cache")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/minimum-moves-to-equal-array-elements-ii "Minimum Moves to Equal Array Elements II")
+
 ## 461. Hamming Distance (Easy)
 
 <p>The <a href="https://en.wikipedia.org/wiki/Hamming_distance" target="_blank">Hamming distance</a> between two integers is the number of positions at which the corresponding bits are different.</p>

problems/happy-number/README.md

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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/bitwise-and-of-numbers-range "Bitwise AND of Numbers Range")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/remove-linked-list-elements "Remove Linked List Elements")
+
 ## 202. Happy Number (Easy)
 
 <p>Write an algorithm to determine if a number is &quot;happy&quot;.</p>

problems/heaters/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/ones-and-zeroes "Ones and Zeroes")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/number-complement "Number Complement")
+
 ## 475. Heaters (Easy)
 
 <p>Winter is coming! Your first job during the contest is to design a standard heater with fixed warm radius to warm all the houses.</p>

problems/house-robber-iii/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/palindrome-pairs "Palindrome Pairs")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/counting-bits "Counting Bits")
+
 ## 337. House Robber III (Medium)
 
 <p>The thief has found himself a new place for his thievery again. There is only one entrance to this area, called the &quot;root.&quot; Besides the root, each house has one and only one parent house. After a tour, the smart thief realized that &quot;all houses in this place forms a binary tree&quot;. It will automatically contact the police if two directly-linked houses were broken into on the same night.</p>

problems/house-robber/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/rising-temperature "Rising Temperature")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/binary-tree-right-side-view "Binary Tree Right Side View")
+
 ## 198. House Robber (Easy)
 
 <p>You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them is that adjacent houses have security system connected and <b>it will automatically contact the police if two adjacent houses were broken into on the same night</b>.</p>

problems/human-traffic-of-stadium/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/non-negative-integers-without-consecutive-ones "Non-negative Integers without Consecutive Ones")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/friend-requests-ii-who-has-the-most-friends "Friend Requests II: Who Has the Most Friends")
+
 ## 601. Human Traffic of Stadium (Hard)
 
 <p>X city built a new stadium, each day many people visit it and the stats are saved as these columns: <b>id</b>, <b>date</b>, <b>people</b>

problems/image-smoother/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/remove-9 "Remove 9")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/maximum-width-of-binary-tree "Maximum Width of Binary Tree")
+
 ## 661. Image Smoother (Easy)
 
 <p>Given a 2D integer matrix M representing the gray scale of an image, you need to design a smoother to make the gray scale of each cell becomes the average gray scale (rounding down) of all the 8 surrounding cells and itself.  If a cell has less than 8 surrounding cells, then use as many as you can.</p>

problems/implement-magic-dictionary/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/cut-off-trees-for-golf-event "Cut Off Trees for Golf Event")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/map-sum-pairs "Map Sum Pairs")
+
 ## 676. Implement Magic Dictionary (Medium)
 
 <p>

problems/implement-queue-using-stacks/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/power-of-two "Power of Two")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/number-of-digit-one "Number of Digit One")
+
 ## 232. Implement Queue using Stacks (Easy)
 
 <p>Implement the following operations of a queue using stacks.</p>

problems/implement-rand10-using-rand7/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/convex-polygon "Convex Polygon")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/encode-string-with-shortest-length "Encode String with Shortest Length")
+
 ## 470. Implement Rand10() Using Rand7() (Medium)
 
 <p>Given a function <code>rand7</code> which generates a uniform random integer in the range 1 to 7, write a function <code>rand10</code>&nbsp;which generates a uniform random integer in the range 1 to 10.</p>

problems/implement-stack-using-queues/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/basic-calculator "Basic Calculator")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/invert-binary-tree "Invert Binary Tree")
+
 ## 225. Implement Stack using Queues (Easy)
 
 <p>Implement the following operations of a stack using queues.</p>

problems/implement-strstr/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/remove-element "Remove Element")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/divide-two-integers "Divide Two Integers")
+
 ## 28. Implement strStr() (Easy)
 
 <p>Implement <a href="http://www.cplusplus.com/reference/cstring/strstr/" target="_blank">strStr()</a>.</p>

problems/implement-trie-prefix-tree/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/course-schedule "Course Schedule")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/minimum-size-subarray-sum "Minimum Size Subarray Sum")
+
 ## 208. Implement Trie (Prefix Tree) (Medium)
 
 <p>Implement a trie with <code>insert</code>, <code>search</code>, and <code>startsWith</code> methods.</p>

problems/increasing-triplet-subsequence/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/largest-bst-subtree "Largest BST Subtree")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/self-crossing "Self Crossing")
+
 ## 334. Increasing Triplet Subsequence (Medium)
 
 <p>Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array.</p>

problems/inorder-successor-in-bst-ii/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/fibonacci-number "Fibonacci Number")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/find-bottom-left-tree-value "Find Bottom Left Tree Value")
+
 ## 510. Inorder Successor in BST II (Medium)
 
 

problems/inorder-successor-in-bst/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/peeking-iterator "Peeking Iterator")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/walls-and-gates "Walls and Gates")
+
 ## 285. Inorder Successor in BST (Medium)
 
 

problems/insert-delete-getrandom-o1-duplicates-allowed/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/insert-delete-getrandom-o1 "Insert Delete GetRandom O(1)")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/linked-list-random-node "Linked List Random Node")
+
 ## 381. Insert Delete GetRandom O(1) - Duplicates allowed (Hard)
 
 <p>Design a data structure that supports all following operations in <i>average</i> <b>O(1)</b> time.</p>

problems/insert-delete-getrandom-o1/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/design-phone-directory "Design Phone Directory")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/insert-delete-getrandom-o1-duplicates-allowed "Insert Delete GetRandom O(1) - Duplicates allowed")
+
 ## 380. Insert Delete GetRandom O(1) (Medium)
 
 <p>Design a data structure that supports all following operations in <i>average</i> <b>O(1)</b> time.</p>

problems/insert-interval/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/merge-intervals "Merge Intervals")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/length-of-last-word "Length of Last Word")
+
 ## 57. Insert Interval (Hard)
 
 <p>Given a set of <em>non-overlapping</em> intervals, insert a new interval into the intervals (merge if necessary).</p>

problems/insert-into-a-binary-search-tree/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/search-in-a-binary-search-tree "Search in a Binary Search Tree")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/search-in-a-sorted-array-of-unknown-size "Search in a Sorted Array of Unknown Size")
+
 ## 701. Insert into a Binary Search Tree (Medium)
 
 <p>Given the root node of a binary search tree (BST) and a value to be inserted into the tree,&nbsp;insert the value into the BST. Return the root node of the BST after the insertion. It is guaranteed that the new value does not exist in the original BST.</p>

problems/insert-into-a-cyclic-sorted-list/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/design-linked-list "Design Linked List")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/to-lower-case "To Lower Case")
+
 ## 708. Insert into a Cyclic Sorted List (Medium)
 
 

problems/insertion-sort-list/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/lru-cache "LRU Cache")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/sort-list "Sort List")
+
 ## 147. Insertion Sort List (Medium)
 
 <p>Sort a linked list using insertion sort.</p>

problems/integer-replacement/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/rotate-function "Rotate Function")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/random-pick-index "Random Pick Index")
+
 ## 397. Integer Replacement (Medium)
 
 <p>

problems/integer-to-roman/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/container-with-most-water "Container With Most Water")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/roman-to-integer "Roman to Integer")
+
 ## 12. Integer to Roman (Medium)
 
 <p>Roman numerals are represented by seven different symbols:&nbsp;<code>I</code>, <code>V</code>, <code>X</code>, <code>L</code>, <code>C</code>, <code>D</code> and <code>M</code>.</p>

problems/intersection-of-two-arrays-ii/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/intersection-of-two-arrays "Intersection of Two Arrays")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/android-unlock-patterns "Android Unlock Patterns")
+
 ## 350. Intersection of Two Arrays II (Easy)
 
 <p>Given two arrays, write a function to compute their intersection.</p>

problems/intersection-of-two-arrays/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/design-tic-tac-toe "Design Tic-Tac-Toe")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/intersection-of-two-arrays-ii "Intersection of Two Arrays II")
+
 ## 349. Intersection of Two Arrays (Easy)
 
 <p>Given two arrays, write a function to compute their intersection.</p>

problems/intersection-of-two-linked-lists/README.md

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 <!--|@home      https://github.com/openset/leetcode                        |-->
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+[< Previous](https://github.com/openset/leetcode/tree/master/problems/longest-substring-with-at-most-two-distinct-characters "Longest Substring with At Most Two Distinct Characters")
+　　　　　　　　　　　　　　　　
+[Next >](https://github.com/openset/leetcode/tree/master/problems/one-edit-distance "One Edit Distance")
+
 ## 160. Intersection of Two Linked Lists (Easy)
 
 <p>Write a program to find the node at which the intersection of two singly linked lists begins.</p>